I'm trying to join my friends minecraft realm but whenever i try this always pops up please help! (i'm on a mac)?

I'm trying to join my friends minecraft realm but whenever i try this always pops up please help! (i'm on a mac)? I m trying to join my friends minecraft realm but whenever i try this always pops up please help i m on a mac

caroline 01.06.2017

Switch to pc.

oskaras 01.06.2017